1969 Volume 38 Issue 1 Pages 65-71
In the adhesion of metal wthe ratio ofith polar high polymer adhesive, electrostatic forces i.e. image induction forces are created between the dipoles of adhesive and the charges induced on the surface of base metal. These forces are assumed to take part in adhesive force. Now, if adhesion is performed with an adhesive of which the dipoles are oriented, adhesive strength will change according to the degree of orientation. The present study was undertaken to ascertain the matter mentioned above and prove the existence and characteristics of image induction force.
Polyvinyl chloride (PVC) and polyethylene (PE) were used as adhesive agents. Adhesion was performed by heating the bonded part where the adhesive was applied. In order to orient the dipoles, the D.C. voltage was applied on the bonded part during bonding process and the effect of the D.C. electric field on adhesive strength was examined.
The results are summarized as follows:
If the electric field was made to act on PVC during bonding process, the test specimen was found to fracture at the ⊕ side of the voltage applied on adhesive-metal interface and it became evident that the adhesive strength of ⊕ side interface would increase and that of Θ side interface would decrease. The influence of the electric field at room temperature on adhesive strength was not observed.
Referring to PE, the influence of the electric field during bonding process on adhesive strength was not observed.
It is to be noted that PVC is a polar high polymer and PE is a non-polar one. If free ions are contained in ahesive, it should be taken into account that these ions will have the same effect as that of the charges of dipoles.